import React, {Component} from 'react';
import {withRouter} from 'react-router-dom'

class Header extends Component {

  back = () => {
    this.props.history.goBack()
  }
  forward = () => {
    this.props.history.goForward()
  }
  go = () => {
    this.props.history.go(-2)
  }

  render() {
    console.log('Header组件收到的props是', this.props)
    return (
      <div className="page-header">
        <h2>React Router Demo</h2>
        <button onClick={this.back}>回退</button>&nbsp;
        <button onClick={this.forward}>前进</button>&nbsp;
        <button onClick={this.go}>go</button>
      </div>
    );
  }
}
export default withRouter(Header)

// withRouter可以加工一般组件，让一般组件具备路由组件所特有的API
// withRouter的返回值是一个新组件